When was the automatic computer invented?

Charles Babbage invented one but never built it in the
1830s.

John Vincent Atanasoff invented one in 1936 and built it
by 1942.

The modern computer was invented sometime between 1943 and
1945 on Project PX (the US Army project to build ENIAC), but
nobody knows who was the inventor(s). A prototype was first built
in Manchester, England in 1948.